The school says there is a negligable difference but it could help because you have a writing sample and grades by August.

Could hurt if your grades suck.

Also, LET ME IN.

That's the key thing. I think it can help because you have grades, more classes, etc, but it can hurt if those grades aren't so great! I know 2Ls who had jobs before they even got their 1L grades, so it's can be a bit of a gamble.

Off campus! I'm biased because I love living alone and wouldn't live in a dorm if you paid me. That said, I know people who really like the LC and now that it's gotten cold it would be convenient to just roll out of bed and walk across the quad. The benefits of off campus definitely outweigh the drawbacks, to me, but ymmv. Feel free to ask any particular housing questions, though I think most of us on here live off campus. At some point they'll send you info about "Housing Ambassadors", who live in various housing options and will also answer your questions. Make sure you take advantage of them too.